Pratt & Whitney build waste heat recovery plant at pellet mill

As a way to enable Canadian pellet mill Nechako Green Energy Ltd. to make the most of its waste products, Pratt & Whitney Power Systems will install a 2-megawatt (MW) biomass waste heat recovery plant at the Vanderhoof, British Columbia facility.

To be built by subsidiary Turboden, which became a part of Pratt & Whitney about two years ago, the Organic Rankine Cycle unit will provide the 140,000-metric ton pellet plant with power. It will use thermal oil from an existing biomass system to burn the mill’s residual hog fuel and waste bark, which would otherwise be landfilled.

Turboden Director Alessandro Foresti said the pellet facility is a good fit for the system because it already employs a thermal oil boiler. “It’s a very good match for our system—quite an ideal situation,” he said. It’s easy to operate and safe, he said, and can usually run unattended.”

While this installation marks the first ORC in a forest products facility in North America, Turboden is well-known in the European forest industry. “We have over 250 plants in operation, and the great majority of them are in the forest industry,” Foresti said.

In Europe, incentives to install these kinds of systems are much better than in North America, Foresti pointed out, but the cost of residual woody biomass is much lower in North America than in Europe. He said he believes the installation of ORCs in North America is going to increase, but British Columbia in particular offers great opportunity because of its large concentration of sawmills. “In Europe installations are typically between 1 and 1.5 MW, but in the U.S. we’ll see bigger units,” he said. “For biomass applications we can supply up to 5 MW.”

The Nechako Green Energy plant should be up and running by the end of next year, he added.

The installation of the Turboden ORC unit is being funded in part by a contribution from the Investments in Forest Industry Transformation program, an initiative by Natural Resources Canada to invest in innovative technologies to help transform Canada’s forest sector.